The present invention relates to a scaffold structure as disclosed in claim 1.
Existing scaffolds are ill-suited for use in connection with light exterior work such as house painting, applying weatherstripping to windows or the like in those cases where the performer of the task is not going to remain in the same place for very long.
This is especially the case when the underlying surface is undulating or uneven, since in that event a scaffold cannot be moved by being shifted via wheels mounted on the scaffold. In general, it takes too long to move and re-erect a scaffold in order to adapt it to the underlying surface.
When painting a house wall, where the ground is uneven, which is often the case for private houses, as a rule ladders are used, as usually it is only possible to gain access with an access platform on one or perhaps two sides of the house.
European Patent Publication EP A1-0 330 642 makes known an arrangement for cleaning windows where a platform is arranged on a ladder. This platform can be moved up and down, and the ladder can be moved sideways along a wall surface. This arrangement normally requires a fixed assembly and is not very suitable for dismantling, moving and reassembly.
U.S. Pat. No. 3,620,332 makes known a ladder of the steps type where the step supporting legs are bent outwards at the bottom so as to obtain a greater distance between the legs, thereby increasing stability.
DT 2442069 A1 makes known ladder and steps embodiments, including a ladder where the upper end of the ladder legs is bent inwards in the form of a wall rest to enable the ladder to be put up having a greater distance to the wall, especially at the top.
European Patent Publication EP 0 355 504 A1 makes known an extension piece which can be mounted on a ladder at the upper end in order to increase the distance to the wall at the top of the ladder.
DT 25 06 528 A1 makes known a platform which, with the aid of a screw, spirals upwards on a fixed ladder. This device normally requires a fixed assembly and is not very suitable for dismantling, moving and reassembling.
U.S. Pat. No. 715,944 makes known a ladder which is put up almost vertically. The ladder has a spacer at the top to create distance from the wall to ensure that there is room for the work platform which runs up and down on the inside of the ladder. At the bottom, two stabilising legs are mounted for lateral stabilisation and to prevent the structure from falling outwards from the wall.
GB 2 12 2572 makes known a ladder which is put up almost vertically. The ladder has a spacer at the top to create distance from the wall to ensure that there is room for the work platform which runs up and down on the inside of the ladder. At the bottom of the ladder there are fixed feet which face backwards in order to prevent the structure from falling outwards from the wall.
U.S. Pat. No. 3,760,902 makes known a ladder which is put up almost vertically. The ladder has a spacer at the top to create distance from the wall to ensure that there is room for the work platform which runs up and down on the inside of the ladder. At the bottom of the ladder there are fixed feet which face backwards and outwards in order to prevent the structure from falling outwards from the wall and to provide lateral stability.
None of the aforementioned publications describe arrangements which are suitable for laterally inclined underlying surfaces.
The object of the present invention is to obviate the drawbacks of the aforementioned arrangements and provide a scaffold which via its structure and function will automatically adjust to the majority of forms of uneven underlying surfaces.
This is achieved by means of a scaffold structure of the type mentioned above whose characterising features are set forth in claim 1.
Thus, the invention relates to a scaffold which consists of two separate legs and a platform.
Each of the legs is in contact with the ground via preferably just one point and the wall at one point. This means that the legs can without additional measures be placed close to a wall despite an uneven and undulating underlying surface.
In this way, both legs can be positioned side by side in parallel relation, and if the underlying surface is uneven will, if necessary, be on different levels.
The legs can be produced in different lengths, e.g., 2 meters, 3.5 meters and 5 meters, so as to be capable of being used for walls of different heights.
The platform is mounted horizontally and in movable interaction with the legs.
The legs have the facility of being mounted on the platform at levels different from one another, and with variable width, depending upon what the ground and the wall call for. When the differences in level sideways are very great, two legs of different lengths can be used.
The platform will then be capable of being moved up and down along the legs with the aid of a winch, rack and pinion, by being lifted manually or in another technically known way, manually or motor-driven.
If necessary, a safety brake can be incorporated which will act as an extra safety mechanism if, e.g., the wire should snap when, for instance, the platform is being winched up.
The user can ascend and descend by being on the platform and hoisting/running himself up and down, or by being on the ground and hoisting/running the platform up and down in order to then enter it with the aid of, e.g., a ladder.
Additional features of the invention are set forth in the other dependent claims.